It could be a prank gone wrong. Maybe Loki or another mischievous character played a trick on Thor that involved some sort of potion or spell that made him vomit. This would add an element of humor and sibling rivalry to the fanfic.
Stress might be a factor. Thor has a lot on his plate, like protecting the realms and dealing with the complex relationships within the Avengers. High stress levels could potentially make him physically ill, such as vomiting. This could be a more serious - toned fanfic that delves into Thor's mental state.
Another idea is that Thor used his powers in an extreme way. For example, he summoned a huge amount of lightning and it drained his energy. This energy drain could have had an impact on his physical well - being, including making him nauseous and causing him to vomit. It could be a way to explore the limits of his powers and how they can have negative consequences on his body.
One possible reason could be that he was poisoned. In the wizarding world, there are many dark spells and potions that could cause such a reaction. Another reason might be extreme motion sickness if he was on a wild magical ride, like on a particularly unruly broomstick or a flying magical creature.
It could also be about narrative tension. Fanfic authors want to keep the story interesting. By having the Avengers be 'dicks' to Tony, they create a source of conflict. This conflict can drive the story forward, whether it's leading to Tony leaving the team for a while, or him trying to fix the relationships. It gives the author more room to explore different emotions and plot developments, like Tony's journey to regain the trust and respect of his fellow Avengers.
Well, in the official Marvel universe, there's no indication that the Avengers sit around watching Thor fanfic. Fanfic is more of a thing for fans in our world, not something the characters themselves would engage with in the main storylines.
One possible reason is that Peter's quick rise to popularity among the public might make the Avengers jealous. They've been around for a long time, and suddenly this young kid is getting all the attention.
In fanfic, sometimes the writers want to create drama. By making the Avengers assholes to Tony, they can build up conflict. It could also be related to past events that the fanfic author has created. Maybe Tony made a mistake in the past that the other Avengers can't forgive, even though it was an accident or done with good intentions, and they keep treating him badly.
One possible reason could be overexertion. Peter Parker is often in high - stress situations in the Avengers. If he uses his powers too much, like constantly swinging around the city or fighting powerful enemies without proper rest, his body might give out and he could collapse. Another reason might be some sort of poisoning. Maybe he gets exposed to a new kind of chemical or toxin during a mission that affects his superhuman physiology.
One possible reason could be a misunderstanding. Maybe Peter accidentally gets involved in something that looks bad to the Avengers, like being in the wrong place at the wrong time during a security breach. So they misjudge him and are mean as a result.
One reason could be to show his vulnerability. Tony Stark is often seen as a strong, confident character. Torturing him in a fanfiction can break down that facade and show his human side, his fears, and how he copes under extreme pressure.
Food poisoning is a common reason. Eating spoiled or contaminated food can make the stomach reject it through vomiting. For example, if you eat raw or undercooked meat that has bacteria in it.